Centrica plc (LSE: CNA) is a large multinational utility company, based in the United Kingdom but also with interests in North America. Centrica is the largest supplier of gas to domestic customers in the UK, and one of the largest suppliers of electricity, operating under the trading names "Scottish Gas" in Scotland and "British Gas" in the rest of the UK. It is listed on the London Stock Exchange and is a constituent of the FTSE 100 Index.

British Gas plc demerged on 17 February 1997 to form two separate companies: Centrica plc and BG plc.

Centrica took over gas sales and gas trading, services and retail businesses, together with the gas production operations in the North and South Morecambe gas fields.

BG plc was renamed BG Group plc in December 1999. BG Group plc uses the British Gas name overseas but it is a separate company to Centrica and has no involvement with the British Gas retail brand in the UK.

Source: Wikipedia